From b5666f70395016a55cc9d57826508b8a346398d0 Mon Sep 17 00:00:00 2001 From: Michael Ellerman Date: Mon, 5 Dec 2005 10:24:33 -0600 Subject: [PATCH] powerpc: Separate usage of KERNELBASE and PAGE_OFFSET This patch separates usage of KERNELBASE and PAGE_OFFSET. I haven't looked at any of the PPC32 code, if we ever want to support Kdump on PPC we'll have to do another audit, ditto for iSeries. This patch makes PAGE_OFFSET the constant, it'll always be 0xC * 1 gazillion for 64-bit. To get a physical address from a virtual one you subtract PAGE_OFFSET, _not_ KERNELBASE. KERNELBASE is the virtual address of the start of the kernel, it's often the same as PAGE_OFFSET, but _might not be_. If you want to know something's offset from the start of the kernel you should subtract KERNELBASE. Signed-off-by: Michael Ellerman Signed-off-by: Paul Mackerras --- arch/powerpc/mm/stab.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) (limited to 'arch/powerpc/mm/stab.c') diff --git a/arch/powerpc/mm/stab.c b/arch/powerpc/mm/stab.c index a18dab0d6b12..82e4951826bc 100644 --- a/arch/powerpc/mm/stab.c +++ b/arch/powerpc/mm/stab.c @@ -40,7 +40,7 @@ static int make_ste(unsigned long stab, unsigned long esid, unsigned long vsid) unsigned long entry, group, old_esid, castout_entry, i; unsigned int global_entry; struct stab_entry *ste, *castout_ste; - unsigned long kernel_segment = (esid << SID_SHIFT) >= KERNELBASE; + unsigned long kernel_segment = (esid << SID_SHIFT) >= PAGE_OFFSET; vsid_data = vsid << STE_VSID_SHIFT; esid_data = esid << SID_SHIFT | STE_ESID_KP | STE_ESID_V; @@ -83,7 +83,7 @@ static int make_ste(unsigned long stab, unsigned long esid, unsigned long vsid) } /* Dont cast out the first kernel segment */ - if ((castout_ste->esid_data & ESID_MASK) != KERNELBASE) + if ((castout_ste->esid_data & ESID_MASK) != PAGE_OFFSET) break; castout_entry = (castout_entry + 1) & 0xf; @@ -251,7 +251,7 @@ void stabs_alloc(void) panic("Unable to allocate segment table for CPU %d.\n", cpu); - newstab += KERNELBASE; + newstab = (unsigned long)__va(newstab); memset((void *)newstab, 0, HW_PAGE_SIZE); @@ -270,11 +270,11 @@ void stabs_alloc(void) */ void stab_initialize(unsigned long stab) { - unsigned long vsid = get_kernel_vsid(KERNELBASE); + unsigned long vsid = get_kernel_vsid(PAGE_OFFSET); unsigned long stabreal; asm volatile("isync; slbia; isync":::"memory"); - make_ste(stab, GET_ESID(KERNELBASE), vsid); + make_ste(stab, GET_ESID(PAGE_OFFSET), vsid); /* Order update */ asm volatile("sync":::"memory"); -- cgit v1.2.2